摘要
通过单宁酸及聚多巴胺涂覆,制备了单宁酸(TA)-聚偏氟乙烯(PVDF)纳滤膜,同时评价了改性膜对刚果红、伊文思蓝、活性嫩黄等染料的分离性能。结果表明,改性后膜表面粗糙度略微增大,亲水性明显增强。同时,改性膜具有水下超疏油的性质,能够完全抵抗水下油污的污染。2wt%TA-PVDF纳滤膜对多种染料的截留率能达到96.5%以上,且对刚果红、伊文思蓝、活性嫩黄等染料的截留通量都超过65.7 L/(m^(2)·h·bar)。另外,改性膜在染料分离时截留通量基本不变,稳定性较强,在工业染料废水处理方面有一定的应用前景。
The tannic acid(TA)-polyvinylidene fluoride(PVDF)nanofiltration membrane is prepared by simply coating tannic acid and polydopamine.The chemical elements and morphology of the nanofiltration membrane surface are characterized by infrared spectroscopy(ATRFTIR),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),and atomic force microscopy(AFM).Meanwhile,the hydrophilicity and underwater anti-oil-adhesion performance of the modified membrane are also evaluated.Besides,the separation performance for dyes such as Direct red,Evans blue,Congo red,Reactive yellow,and Brilliant blue is explored.The result shows that the surface roughness of the obtained membrane increases slightly after modification.With the increase of TA concentration,the hydrophilicity of the membrane surface is significantly enhanced.When the TA concentration reaches 2wt%,the surface hydrophilicity of the prepared TAPVDF nanofiltration membrane is almost stable,and the water contact angle of the modified membrane is 44.6°.Additionally,the obtained membrane with the underwater oil contact angle of 157.2°is characterized as a superoleophobic one.There is a strong interaction between the modified membrane and water molecules.On account of the hydration layer formed on the membrane surface,the obtained membrane can completely resist the contamination of oil under the water.The rejection rate of 2wt%TA-PVDF nanofiltration membrane is more than 96.5%for several dyes,and its permeating fluxes of Direct red,Evans blue,Congo red,Reactive yellow,and Brilliant blue all exceed 65.7 L/(m^(2)·h·bar).In addition,the modified membrane keeps the permeance nearly unchanged during the dyes'separation process,exhibiting strong stability for dyes separation.Compared to the works published recently,the prepared nanofiltration membrane with 97%rejection rate for Congo red has a higher permeating flux.The obtained membrane shows a superior separation capacity and efficiency for the dyes,demonstrating a good application prospect in industrial dye wastewater separation.
作者
江琴
刘子瑜
赵濉
Qin JIANG;Ziyu LIU;Sui ZHAO(Key Laboratory of Photochemical Conversion and Optoelectronic Materials,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《过程工程学报》
CAS
CSCD
北大核心
2022年第1期89-96,共8页
The Chinese Journal of Process Engineering
基金
国家自然科学基金资助项目(编号:22075304)。
关键词
纳滤膜
单宁酸
聚多巴胺
染料分离
高通量
nanofiltration membrane
tannic acid
polydopamine
dye separation
high water flux
